Narrative:

Before landing; we did 2 orbits over the field to determine suitability for landing. The landing zone was large; about 175 yards long and 80 yards wide. Based on more than 13 years of military; commercial; and EMS flying experience; this landing zone was very typical for off-airport helicopter operations. There were wires on the north; south and east sides of the field. There were trees on the west side. The topography of the zone was quite level and considering the large size of the zone; I determined it to be a very suitable landing area. The winds were reported to be south south-east at 8 KTS. I planned my approach to the south into the wind. We flew a steep approach. My tactical flight officer (tfo) called me clear over the wires on the left side of the aircraft and I ensured we were clear of obstacles on the right. We landed uneventfully on the south end of the landing zone. Prior to first departure out of the lz; I turned the helicopter around and hover-taxied back to the north end of the zone to facilitate a departure into the wind (to the south). When done with the fly over; we landed uneventfully back in the landing zone the same way as described above on the first landing. I again turned the aircraft and hover-taxied to the north end of the field to depart in a southerly direction. After reaching the north end; I was turning the aircraft around with a left pedal turn. I saw a large portable advertising sign in the field and told my tfo; 'I have the sign in sight. I'm bringing the tail to the right. We're clear of the sign.' as I completed the pedal turn; I felt a 'thud' briefly. There were no unusual cockpit indications; vibrations; or other unusual handling characteristics. My first thought was that a stick or branch had been blown upward possibly underneath or maybe even into the tail rotor. My tfo then noticed a wire dangling from a pole by the road near the sign mentioned above. I landed and shut down the helicopter. On examination; it was apparent that a telephone wire had made contact with the rotor system. This small telephone wire was strung diagonally across the northeast corner of the landing zone. Neither of us ever saw that wire running diagonally across the corner of the zone. This wire was no factor to the helicopter's landing flight path. Due to the viewing angle of this wire while taxiing northbound with many more prominent wires and trees in the background; spotting this wire was extremely difficult. I believe a contributing factor may have been that I had just moments before; taxied the aircraft in the same manner and did not hit anything. Also; the sign was much more prominent and may have drawn my attention more to it than to the wire above. Also; this wire was smaller than many of the others and the only wire strung diagonally across the zone rather than around the perimeter. Lastly; the background made this wire nearly impossible to see. It is hard to pick out even after the event and knowing it is there. We were lucky in that there was no substantial damage and no one was hurt or injured. It may heighten the awareness of others to read this. Expect the unexpected. We are trained to look not only for the wires but for the poles. These two poles; with a wire running diagonally; were an unusual place to have a wire but I for one will look closer and longer for wires in unusual; unexpected locations or where they may be masked from view by either the background or the sun.

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Original NASA ASRS Text

Title: A helicopter pilot reported striking a telephone line with the tail rotor during departure.

Narrative: Before landing; we did 2 orbits over the field to determine suitability for landing. The landing zone was large; about 175 yards long and 80 yards wide. Based on more than 13 years of military; commercial; and EMS flying experience; this landing zone was very typical for off-airport helicopter operations. There were wires on the North; South and East sides of the field. There were trees on the West side. The topography of the zone was quite level and considering the large size of the zone; I determined it to be a very suitable landing area. The winds were reported to be South South-East at 8 KTS. I planned my approach to the South into the wind. We flew a steep approach. My Tactical Flight Officer (TFO) called me clear over the wires on the left side of the aircraft and I ensured we were clear of obstacles on the right. We landed uneventfully on the South end of the landing zone. Prior to first departure out of the LZ; I turned the helicopter around and hover-taxied back to the North end of the zone to facilitate a departure into the wind (to the South). When done with the fly over; we landed uneventfully back in the landing zone the same way as described above on the first landing. I again turned the aircraft and hover-taxied to the North end of the field to depart in a Southerly direction. After reaching the North end; I was turning the aircraft around with a left pedal turn. I saw a large portable advertising sign in the field and told my TFO; 'I have the sign in sight. I'm bringing the tail to the right. We're clear of the sign.' As I completed the pedal turn; I felt a 'thud' briefly. There were no unusual cockpit indications; vibrations; or other unusual handling characteristics. My first thought was that a stick or branch had been blown upward possibly underneath or maybe even into the tail rotor. My TFO then noticed a wire dangling from a pole by the road near the sign mentioned above. I landed and shut down the helicopter. On examination; it was apparent that a telephone wire had made contact with the rotor system. This small telephone wire was strung diagonally across the Northeast corner of the landing zone. Neither of us ever saw that wire running diagonally across the corner of the zone. This wire was no factor to the helicopter's landing flight path. Due to the viewing angle of this wire while taxiing Northbound with many more prominent wires and trees in the background; spotting this wire was extremely difficult. I believe a contributing factor may have been that I had just moments before; taxied the aircraft in the same manner and did not hit anything. Also; the sign was much more prominent and may have drawn my attention more to it than to the wire above. Also; this wire was smaller than many of the others and the only wire strung diagonally across the zone rather than around the perimeter. Lastly; the background made this wire nearly impossible to see. It is hard to pick out even after the event and knowing it is there. We were lucky in that there was no substantial damage and no one was hurt or injured. It may heighten the awareness of others to read this. Expect the unexpected. We are trained to look not only for the wires but for the poles. These two poles; with a wire running diagonally; were an unusual place to have a wire but I for one will look closer and longer for wires in unusual; unexpected locations or where they may be masked from view by either the background or the sun.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.